The ultimate goal of this Mentored Career Development Award (K23) is to provide the applicant with the training and experience necessary to develop an independent program of research focused on adapting evidence-based child treatment (EBTs) programs for use in community practice settings. The application focuses on adapting a treatment program for children with internalizing disorders by addressing client symptom and provider-related factors. The award will provide for in-depth training that will expand the applicant's expertise in outcome research and treatment development in several specific ways. First, he will be trained in treatment approaches that address externalizing comorbidity. In addition, he will receive training in methodologies to identify and assess provider, agency, and system factors that will facilitate the adaptation of evidence-based treatment program. Furthermore, he will receive training in advanced statistical and methodological topics that will facilitate his future research. Finally, he will receive training in the ethical conduct of research. The research plan has two phases: Early Adaptation/Safety and Feasibility Pilot. The Early Adaptation/Safety phase involves (a) focus groups with stakeholders to provide possible ways of adapting EBTs to better fit the clients, providers, and agency and (b) eight single-case design studies piloting the preliminary version of the adapted treatment. The Feasibility Pilot phase involves (a) a small pilot trial (n=58) comparing the adapted EBT to usual care in the clinic and (b) post-project focus groups with agency stakeholders to assess perceptions of the research process and to identify ways of further adapting the treatment program. Data from the projects will be used as pilot data for an RO1 application to NIMH to test the adapted treatment in a larger comparative design.